P0012 A Camshaft Position Timing Over-Retarded Bank 1
P0012 is a generic OBD2 powertrain diagnostic trouble code for a camshaft position timing over-retarded bank 1. The code identifies the system or circuit the engine computer flagged, but diagnosis still depends on vehicle symptoms, freeze-frame data, and related codes.
Timing, camshaft, and crankshaft correlation faults can cause stalling, no-starts, poor power, and engine damage if the underlying issue is mechanical.
Common symptoms
- Check engine light
- Hard start or no-start
- Rough idle
- Poor acceleration
- Stalling
Likely causes
- Low or dirty oil
- Failing cam/crank sensor
- Timing chain or belt wear
- Variable valve timing solenoid fault
- Wiring or connector issue
What to check before replacing parts
Check oil level and condition
Inspect cam/crank sensor wiring
Review live cam/crank data
Check VVT solenoid operation
Verify mechanical timing if correlation codes remain
A code points at the system, not always the failed part. Add your vehicle, mileage, symptoms, and whether the check engine light is steady or flashing so the AI diagnostic can narrow the next step.